How to recognise a good programmer

How do you recognise good programmers if you’re a business guy?

It’s not as easy as it sounds. CV experience is only of limited use here, because great programmers don’t always have the “official” experience to demonstrate that they’re great. In fact, a lot of that CV experience can be misleading. Yet there are a number of subtle cues that you can get, even from the CV, to figure out whether someone’s a great programmer.

I consider myself to be a pretty good programmer. At the same time, I’ve spent a fair amount of time on the business side of the fence, filtering technical CVs for projects, interviewing people, etc. Thanks to this, I think I have a bit of experience in recognising good programmers, and I want to share it in this article, in the hope that it may help other “business guys” to recognise good programmers. And, who knows, perhaps some programmers who have the potential to be good but haven’t really exploited this can also read this and realise what they need to do to become good (although, as I’ll argue, that’s definitely not accessible to all programmers!).

In his article The 18 mistakes that kill startups, Paul Graham makes the following point:

“… what killed most of the startups in the e-commerce business back in the 90s, it was bad programmers. A lot of those companies were started by business guys who thought the way startups worked was that you had some clever idea and then hired programmers to implement it. That’s actually much harder than it sounds—almost impossibly hard in fact—because business guys can’t tell which are the good programmers. They don’t even get a shot at the best ones, because no one really good wants a job implementing the vision of a business guy.

In practice what happens is that the business guys choose people they think are good programmers (it says here on his resume that he’s a Microsoft Certified Developer) but who aren’t. Then they’re mystified to find that their startup lumbers along like a World War II bomber while their competitors scream past like jet fighters. This kind of startup is in the same position as a big company, but without the advantages.

So how do you pick good programmers if you’re not a programmer? I don’t think there’s an answer. I was about to say you’d have to find a good programmer to help you hire people. But if you can’t recognize good programmers, how would you even do that?”

I disagree with Mr Graham on this one. I think there are a number of very strong indicators of a “good programmer” (and, conversely, strong indicators of a “not-so-good programmer”) that even a business guy can recognise. I’ll summarise some key indicators and counter-indicators in a list at the end of the article.

#1 : Passion

In my corporate experience, I met a kind of technical guy I’d never met before: the career programmer. This is a person who’s doing IT because they think it’s a good career. They don’t do any programming in their spare time. They’re shocked when they find out I have a LAN and 3 computers at home. They just do it at work. They don’t learn new stuff unless sent on a training program (or motivated by the need to get a job that requires that technology). They do “programming” as a day job. They don’t really want to talk about it outside of work. When they do, they talk with a distinctive lack of enthusiasm. Basically, they lack passion.

I believe that good developers are always passionate about programming. Good developers would do some programming even if they weren’t being paid for it. Good programmers will have a tendency to talk your ear off about some technical detail of what they’re working on (but while clearly believing, sincerely, that what they’re talking about is really worth talking about). Some people might see that as maladapted social skills (which it is), but if you want to recognise a good developer, this passion for what they’re doing at the expense of social smoothness is a very strong indicator. Can you get this guy to excitedly chat up a technology that he’s using, for a whole half hour, without losing steam? Then you might be onto a winner.

#2 : Self-teaching and love of learning

Programming is the ultimate moving target. Not a year goes by without some new technology robbing an old, established standard blind and changing half the development universe. This is not to say that all good programmers pick up these changes and ride the bleeding edge. However, there’s a class of programmers that will never, ever pick up a new technology unless forced to, because they don’t like learning new stuff. These programmers will typically have learnt programming at university, and expect to get by on whatever skills they picked up there, plus whatever courses their company is willing to send them on.

If you’re thinking of hiring someone as a programmer, and he ever utters the words “I can work with that, just send me on a training course for a week and I’ll be good at it”, don’t hire that guy. A good programmer doesn’t need a training course to learn a new technology. In fact, the great programmer will be the one talking your ear off about a new technology that you haven’t even heard of, explaining to you why you must use it in your business, even if none of your staff knows how to use it. Even if it’s a technology he doesn’t know how to use yet.

#3 : Intelligence

Some business people assume that lack of social tact and lack of intelligence are the same. Actually, intelligence has several facets, and emotional/social intelligence is only one of them. Good programmers aren’t dumb. Ever. In fact, good programmers are usually amongst the smartest people you know. Many of them will actually have pretty good social skills too. The cliché of the programmer who’s incapable of having a conversation is just that - a cliché. I’ve been to a few meetings of the London Ruby User Group and I can say that with only a very few exceptions, most people there are smart, talkative, sociable, have varied interests, etc. You wouldn’t look at them chattering away in the pub and think “what a bunch of geeks!” - at least until you approach a group and realise they’re talking about the best way to design a RESTful application with a heavy UI frontend.

This doesn’t mean that they’ll all feel comfortable in every social context. But it does mean that if the context is comfortable and non-threatening enough, you’ll be able to have as great a conversation with them as you would with the most “socially enabled” people (perhaps better, since most good programmers I know like their conversation to revolve around actually useful topics, rather than just inane banter).

Don’t ever hire a dumb person thinking they’re a good developer. They’re not. If you can’t have a great conversation with them in a relaxed social context, they’re very likely not a good programmer. On the other hand, anyone who’s clearly very smart at the very least has a strong potential to be a good or great programmer.

#4 : Hidden experience

This is correlated with the “Passion” point, but it is such a strong indicator that I’d like to emphasise it with its own point.

I started programming when I was about 9, on a Commodore 64. I then migrated onto the PC, did some Pascal. When I was 14 I wrote a raycasting engine in C and Assembler, spent a large amount of time playing with cool graphic effects that you could get your computer to do by messing directly with the video card. This was what I call my “coccoon stage”. When I entered that stage, I was a mediocre programmer, and lacked the confidence to do anything really complicated. When I finished it, I had gained that confidence. I knew that I could code pretty much anything so long as I put my mind to it.

Has that ever appeared on my CV? Nope.

I strongly believe that most good programmers will have a hidden iceberg or two like this that doesn’t appear on their CV or profile. Something they think isn’t really relevant, because it’s not “proper experience”, but which actually represents an awesome accomplishment. A good question to ask a potential “good programmer” in an interview would be “can you tell me about a personal project - even or especially one that’s completely irrelevant - that you did in your spare time, and that’s not on your CV?” If they can’t (unless their CV is 20 pages long), they’re probably not a good programmer. Even a programmer with an exhaustive CV will have some significant projects that are missing from there.

#5 : Variety of technologies

This one’s pretty simple. Because of the love of learning and toying with new technologies that comes with the package of being a “good programmer”, it’s inevitable that any “good programmer” over the age of 22 will be fluent in a dozen different technologies. They can’t help it. Learning a new technology is one of the most fun things a programmer with any passion can do. So they’ll do it all the time, and accumulate a portfolio of things they’ve “played around with”. They may not be experts at all of them, but all decent programmers will be fluent in a large inventory of unrelated technologies.

That “unrelated” bit is the subtle twist. Every half-decent java programmer will be able to list a set of technologies like “Java, J2EE, Ant, XML, SQL, Hibernate, Spring, Struts, EJB, Shell scripting”, etc.. But those are all part of the same technology stack, all directly related to each other. This is possibly hard to recognise for non-programmers, but it is possible to tell whether their technology stack is varied by talking to them about it, and asking them how the different technologies they know relate to each other. Over-specialisation in a single technology stack is an indicator of a not-so-good programmer.

Finally, if some of those technologies are at the bleeding edge, that’s a good positive indicator. For instance, today (November 2007), knowledge of Merb, Flex, RSpec, HAML, UJS, and many others… Please note that these are fairly closely related technologies, so in a couple of years, someone who knows all these will be equivalent to someone familiar with the Java stack listed in the previous paragraph.

Update: As a clarification to this point, there’s in fact two indicators here: variety and bleeding edge. Those are separate indicators. A good variety of technologies across a period of time is a positive indicator, whether or not the technologies are bleeding edge. And bleeding edge technologies are a positive indicator, whether or not there’s a variety of them.

#6 : Formal qualifications

This is more a of non-indicator than a counter-indicator. The key point to outline here is that formal qualifications don’t mean squat when you’re trying to recognise a good programmer. Many good programmers will have a degree in Computer Science. Many won’t. Certifications, like MCSE or SCJP or the like, don’t mean anything either. These are designed to be accessible and desirable to all. The only thing they indicate is a certain level of knowledge of a technology. They’re safeguards that allow technology recruitment people in large corporations to know “ok, this guy knows java, he’s got a certification to prove it” without having to interview them.

If you’re hiring for a small business, or you need really smart developers for a crack team that will implement agile development in your enterprise, you should disregard most formal qualifications as noise. They really don’t tell you very much about whether the programmer is good. Similarly, disregard age. Some programmers are awesome at 18. Others are awesome at 40. You can’t base your decisions about programmer quality on age (though you might decide to hire people around a certain age to have a better fit in the company; please do note that age discrimination is illegal in most countries!).

As a final note to this, in my experience most average or poor programmers start programming at university, for their Computer Science course. Most good programmers started programming long before, and the degree was just a natural continuation of their hobby. If your potential programmer didn’t do any programming before university, and all his experience starts when she got her first job, she’s probably not a good programmer.

Disclaimer

None of the indicators above or below are sure-fire indicators. You will find great programmers who break some of those moulds. However, my view is, you’ll rarely find a great programmer that breaks all of them. Similarly, you may find poor programmers that meet (or appear to meet) some of these criteria. But I do strongly believe that the more of these criteria a programmer meets, the more likely they are to be one of those elusive “good programmers” that, as a business guy, you need to partner with.

The criteria in bullets

So, in summary, here are some indicators and counter-indicators that should help you recognise a good programmer.

Positive indicators:

• Passionate about technology
• Programs as a hobby
• Will talk your ear off on a technical subject if encouraged
• Significant (and often numerous) personal side-projects over the years
• Learns new technologies on his/her own
• Opinionated about which technologies are better for various usages
• Very uncomfortable about the idea of working with a technology he doesn’t believe to be “right”
• Clearly smart, can have great conversations on a variety of topics
• Started programming long before university/work
• Has some hidden “icebergs”, large personal projects under the CV radar
• Knowledge of a large variety of unrelated technologies (may not be on CV)

Negative indicators:

• Programming is a day job
• Don’t really want to “talk shop”, even when encouraged to
• Learns new technologies in company-sponsored courses
• Happy to work with whatever technology you’ve picked, “all technologies are good”
• Doesn’t seem too smart
• Started programming at university
• All programming experience is on the CV
• Focused mainly on one or two technology stacks (e.g. everything to do with developing a java application), with no experience outside of it

I hope these help. Let me know below if you have any comments, or anything to add to them!

Thanks for reading.